This research project is concerned with the study of nucleotide sequence arrangement in eucaryotic genes and how this sequence arrangement relates to gene function. We have chosen the globin genes to study because much is already known about the regulation of these genes in several species and because globin mRNA is easily obtained. Our current interests center on the globin genes for mouse and duck because: 1) much is already known about the processing of the large nuclear RNA precursors to mRNA, 2) the organization of mouse genes appears to be similar to human, 3) mouse strains exist with a variety of globin alleles, 4) duck mRNA appears to initiate translation of globin protein synthesis differently than globins of other species, and 5) duck globins exhibit an anemic shift. We are in the process of cloning globin mRNA sequences via recombinant cDNAs. We will then determine their nucleotide sequences. We will also use the cDNA recombinants to aid in the isolation of globin structural genes from mouse and duck chromosomal DNA. This second phase of recombinant DNAs will also be studied by nucleotide sequence analysis.